JPH06209378A - Voice circuit - Google Patents

Voice circuit

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Publication number
JPH06209378A
JPH06209378A JP50A JP226493A JPH06209378A JP H06209378 A JPH06209378 A JP H06209378A JP 50 A JP50 A JP 50A JP 226493 A JP226493 A JP 226493A JP H06209378 A JPH06209378 A JP H06209378A
Authority
JP
Japan
Prior art keywords
voltage
output
signal
circuit
amplifier
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP50A
Other languages
Japanese (ja)
Other versions
JP2927130B2 (en
Inventor
Itaru Okada
格 岡田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP226493A priority Critical patent/JP2927130B2/en
Publication of JPH06209378A publication Critical patent/JPH06209378A/en
Application granted granted Critical
Publication of JP2927130B2 publication Critical patent/JP2927130B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Abstract

PURPOSE:To provide a device capable of automatically transmitting one of signals preferentially the case of superimposing analog acoustic signals by two signal sources on one signal wire to be transmitted. CONSTITUTION:Call transmission signals and call reception signals from amplifiers 1 and 2 are outputted to a rectifier circuit 3 and the rectifier circuit 3 converts input signals to direct currents and outputs the one with a higher voltage to a charge and discharge circuit 4 at all times. The voltage accompanied by delay due to a time constant set in the fall of the DC voltage is outputted to a comparator 5 at the charge and discharge circuit 4. The comparator 5 outputs a first voltage when the input voltage is higher than a set reference voltage and outputs a second voltage when it is lower to a switching circuit 6. Whether input is to be outputted as it is or to be left as the second voltage is switched by control signals at the switching circuit 6. The amplifier 7 is set at first gain when the output of the switching circuit 6 is the first voltage and at second gain when it is the second voltage and the amplifiers 8 and 9 superimpose the output of the amplifier 7 respectively on the call transmission signals and the call reception signals to amplify the respective signals.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、通信端末のアナログ音
声信号処理に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to analog voice signal processing for communication terminals.

【0002】[0002]

【従来の技術】従来、端末甲と端末乙がTV電話で通話
中に、端末甲側でVTR装置を端末に接続し、甲から乙
に対してビデオテープを用いてプレゼンテーションを行
うような場合、端末甲、端末乙の両方でビデオの音声は
端末から聴取している。
2. Description of the Related Art Conventionally, when a VTR device is connected to a terminal on the side of the terminal A and a terminal A and the terminal B are talking on a TV telephone, and a presentation is given from the party A to the party B using a video tape, Both the terminal A and the terminal B listen to the video sound from the terminal.

【0003】プレゼンテーションを能率よく進めるには
ビデオテープの音声と端末甲側、端末乙側の音声が同時
に伝送できたほうが良い。この場合、端末甲側での音声
同時伝送方法としては2通りある。
In order to efficiently proceed with the presentation, it is preferable that the voice of the video tape and the voice of the terminal A side and the terminal B side can be transmitted at the same time. In this case, there are two methods for simultaneous voice transmission on the side of the terminal.

【0004】一つは、ビデオの音声信号と肉声による送
話信号、ビデオの音声信号と局側からの受話信号を単に
重畳させ、それぞれ送話出力信号、受話出力信号とする
方法がある。
One is a method of simply superimposing a video voice signal and a voice transmission signal by a real voice, and a video voice signal and a reception signal from the station side to form a transmission output signal and a reception output signal, respectively.

【0005】もう1つはスイッチによりビデオの音声信
号と肉声による送話信号、局側からの受話信号とを切り
替える方法である。この方法では甲が必要に応じて手動
で切り換えをする。
The other is a method of switching between a voice signal of video, a transmission signal of a real voice, and a reception signal from the station side by a switch. In this method, the instep is manually switched when necessary.

【0006】[0006]

【発明が解決しようとする課題】上述した従来技術で述
べた方法には下記の欠点がある。
The method described in the above-mentioned prior art has the following drawbacks.

【0007】すなわち、ビデオの音声信号と肉声による
送信信号、ビデオの音声信号と局側からの受話信号を単
に重畳させ、それぞれ送話出力信号、受話出力信号とす
る方法では、ビデオの音声信号と肉声による送話信号、
ビデオの音声信号と局側からの受話信号を同じレベルに
なるように重畳すると、両方とも聞こえるのでその内容
を容易に聞き取ることはできない。また、片方が聞こえ
るようにレベルの差をつければ、もう片方が聞こえなく
なり両方とも聞くという主旨に反する。
That is, in the method of simply superposing the video audio signal and the transmission signal by the real voice, and the video audio signal and the reception signal from the station side to obtain the transmission output signal and the reception output signal, respectively, Voice signal,
If the audio signal of the video and the received signal from the station side are superimposed so that they have the same level, both can be heard, and the contents cannot be easily heard. In addition, it is contrary to the idea that if you set different levels so that you can hear one, you cannot hear the other and listen to both.

【0008】スイッチによりビデオの音声信号と肉声に
よる送話信号、局側からの受話信号を切り替えることに
より両方の信号を伝送する方法は、甲が必要に応じて手
動で切り替えをするので、会話に即応した切り替えがで
きない、甲が切り替えるので乙側の意志が尊重されな
い、長時間使うと手が疲れるなどの欠点がある。
A method of transmitting both signals by switching between a voice signal of a video, a voice transmission signal by a real voice, and a reception signal from the station side by a switch is because A has a manual switch as needed, so There are drawbacks such as not being able to switch in a prompt manner, the intention of the other party not being respected because the instep is switching, and the hands getting tired when used for a long time.

【0009】そこで本発明はビデオの音声信号と肉声に
よる送話信号、局側からの受話信号の切り替えを、甲、
乙の音声のいずれかを検出することにより肉声による送
話信号と局側からの受話信号が優先して伝送されるよう
にして自動制御を行い、手動で切り替えることによる欠
点を解決するために考案されたものである。
Therefore, according to the present invention, switching between a voice signal of a video, a transmission signal by a real voice, and a reception signal from the station side
It was devised to solve the shortcomings of automatic switching by detecting either of B's voices so that the transmitted signal by the real voice and the received signal from the station side are preferentially transmitted and switched manually. It was done.

【0010】[0010]

【課題を解決するための手段】本発明によれば、送話信
号を増幅する第1の増幅器と、局側からの受話信号を増
幅する第2の増幅器と、これら第1,第2の増幅器の出
力を直流電圧に変換して、常にどちらか電圧の高い方を
出力する整流回路と、この整流回路の出力を充電し、放
電時はある時定数をもって、出力電圧が減少する充放電
回路と、この充放電回路の出力を入力とし、基準電圧に
対して、入力電圧が高いと第一のレベルの電圧を出力
し、低いと第二のレベルの電圧を出力する比較器と、こ
の比較器の出力を入力として、入力と同じ電圧をそのま
ま出力する状態と入力電圧に関わらず第二のレベルの電
圧のみを出力する状態を自動制御をオン/オフするため
の信号により切り替えるスイッチ回路と、ビデオ等の音
声信号を入力とし、スイッチ回路の出力を制御入力と
し、制御入力が第二のレベルの電圧の時は聴取するのに
ちょうど良い出力になるような利得であり、第一のレベ
ルの電圧の時は聴取するのに困難なほど振幅を小さくす
る利得で、ビデオ等の音声信号を増幅する第3の増幅器
と、第3の増幅器の出力を肉声による送話信号に重畳す
る回路と、第3の増幅器の出力を局側からの受話信号に
重畳する回路とを含む。
According to the present invention, a first amplifier for amplifying a transmission signal, a second amplifier for amplifying a reception signal from the station side, and these first and second amplifiers are provided. The rectifier circuit that converts the output of DC to DC voltage and always outputs the higher voltage, and the charge and discharge circuit that charges the output of this rectifier circuit and reduces the output voltage with a certain time constant during discharge. , A comparator that receives the output of this charge / discharge circuit as an input, outputs a voltage of a first level when the input voltage is high and outputs a voltage of a second level when the input voltage is low, and this comparator The switch circuit that switches the state of outputting the same voltage as the input as it is and the state of outputting only the voltage of the second level regardless of the input voltage by the signal for turning on / off the automatic control, and the video , Etc. as an input, The output of the switch circuit is the control input, and when the control input is the second level voltage, the gain is such that the output is just good for listening, and it is difficult for the first level voltage to be heard. A third amplifier that amplifies an audio signal such as a video with a gain that reduces the amplitude, a circuit that superimposes the output of the third amplifier on a voice-transmitting signal, and an output of the third amplifier on the local side. And a circuit to be superimposed on the received signal from.

【0011】[0011]

【実施例】次に本発明の実施例について図面を参照して
詳細に説明する。
Embodiments of the present invention will now be described in detail with reference to the drawings.

【0012】図1は本発明の実施例を示すブロック図、
図2は図1における整流回路の回路図である。
FIG. 1 is a block diagram showing an embodiment of the present invention,
FIG. 2 is a circuit diagram of the rectifier circuit in FIG.

【0013】図において、増幅器1は、肉声による送話
信号を入力とし、無信号時の出力は0Vで、増幅率は3
4dBであり、入力信号が−23dBmを越えると出力
信号がクリップする。
In the figure, an amplifier 1 receives a voice transmission signal as an input, an output when there is no signal is 0V, and an amplification factor is 3
It is 4 dB, and when the input signal exceeds -23 dBm, the output signal is clipped.

【0014】増幅器2は局側からの受話信号を入力と
し、無信号時の出力は0Vで、増幅率は20dBであ
り、入力信号が−9dBmを越えると出力信号がクリッ
プする。
The amplifier 2 receives the received signal from the station side, the output when there is no signal is 0 V, the amplification factor is 20 dB, and when the input signal exceeds -9 dBm, the output signal is clipped.

【0015】整流回路3は増幅器1の出力と増幅器2の
出力を入力とし、このそれぞれの入力信号を半波整流方
式により直流電圧に変換して、常にどちらか電圧の高い
方を出力する。図2に示すようにこの回路はダイオード
のワイヤードOR回路であり、入力1(あるいは入力
2)に正の電圧が入力されると、入力2(あるいは入力
1)へは電流は流れずに出力側にのみ正の電圧がかか
る。
The rectifier circuit 3 receives the output of the amplifier 1 and the output of the amplifier 2 and converts the respective input signals into a DC voltage by the half-wave rectification method, and always outputs the higher voltage. As shown in FIG. 2, this circuit is a wired OR circuit of diodes. When a positive voltage is input to input 1 (or input 2), no current flows to input 2 (or input 1) and the output side Only a positive voltage is applied to.

【0016】充放電回路4は、整流回路3の出力を入力
とする抵抗とコンデンサによる充放電回路からなる。そ
の出力特性は、充電時は整流回路3の出力の電圧上昇と
同時に出力電圧が上昇するが、放電時は整流回路の直流
出力電圧が5Vから0Vにまで減少した時に出力電圧が
5Vから1Vにまで減少するのに2秒間かかる時定数を
もって、出力電圧が減少するものである。
The charging / discharging circuit 4 is composed of a charging / discharging circuit having a resistor and a capacitor which receive the output of the rectifier circuit 3 as an input. The output characteristic is that the output voltage rises at the same time as the output voltage of the rectifier circuit 3 increases during charging, but the output voltage changes from 5V to 1V when the DC output voltage of the rectifier circuit decreases from 5V to 0V during discharging. The output voltage decreases with a time constant that takes 2 seconds to decrease.

【0017】比較器5は充放電回路4の出力を入力と
し、基準電圧(1V)に対して、入力電圧が高いと0V
の電圧を出力し、低いと5Vの電圧を出力する。
The comparator 5 receives the output of the charging / discharging circuit 4 as an input, and 0 V when the input voltage is higher than the reference voltage (1 V).
When the voltage is low, a voltage of 5V is output.

【0018】スイッチ回路6は、比較器5の出力を入力
として、その入力と同じ電圧をそのまま出力する状態と
入力電圧に関わらず5Vのみを出力する状態とを自動制
御をオン/オフするための信号により切り替える。
The switch circuit 6 receives the output of the comparator 5 as an input and outputs the same voltage as that input as it is, or outputs only 5 V regardless of the input voltage for turning on / off the automatic control. Switch by signal.

【0019】増幅器7はビデオ等の音声信号を入力とし
て増幅するもので、スイッチ回路6の出力を制御入力と
し、制御入力が5Vの時は0dBの利得であり、0Vの
時は−20dBの利得である。
The amplifier 7 amplifies an audio signal such as video as an input, and uses the output of the switch circuit 6 as a control input. When the control input is 5 V, the gain is 0 dB, and when it is 0 V, the gain is -20 dB. Is.

【0020】増幅器8は増幅器7の出力を肉声による送
話信号に重畳して、送話出力信号として出力する増幅器
であって、肉声による送話信号および増幅器7の出力信
号に対する利得は0dBのものである。
The amplifier 8 is an amplifier which superimposes the output of the amplifier 7 on the voice-transmitting signal by the real voice and outputs it as a voice-transmitting output signal, and the gain for the voice-transmitting signal for the real voice and the output signal of the amplifier 7 is 0 dB. Is.

【0021】増幅器9は、増幅器7の出力を局側からの
受話信号に重畳して、受話出力信号として出力する増幅
器であって、局側からの受話信号に対する利得は0dB
で、増幅器7からの出力信号に対する利得は14dBの
ものである。
The amplifier 9 is an amplifier which superimposes the output of the amplifier 7 on a reception signal from the station side and outputs it as a reception output signal. The gain for the reception signal from the station side is 0 dB.
The gain for the output signal from the amplifier 7 is 14 dB.

【0022】次に本発明の実施例の動作について各状態
別に説明する。
Next, the operation of the embodiment of the present invention will be described for each state.

【0023】1.自動制御がオン状態のとき 1−1.肉声による送話信号および局側からの受信信号
がないとき 増幅器1、および、増幅器2はそれぞれの入力信号が0
Vなので、出力は0Vである。その出力を入力とする整
流回路3の出力は0Vとなり、充放電回路4の出力は0
Vとなり、比較器5には0Vが入力される。比較器5に
入力された電圧は基準電圧の1Vより低いので、5Vの
電圧を出力する。スイッチ回路6は入力された5Vの電
圧をそのまま出力する。増幅器7はスイッチ回路6の出
力である5Vの制御電圧により、増幅度が0dBにな
る。増幅器7に入力されたビデオの音声信号はそのまま
の振幅で出力される。増幅器8、および、増幅器9は増
幅器7のビデオ音声出力をそれぞれ、送話出力信号、受
話出力信号として出力する。
1. When automatic control is on 1-1. When there is no voice-transmitted signal or received signal from the station side, the input signals of amplifier 1 and amplifier 2 are 0
Since it is V, the output is 0V. The output of the rectifier circuit 3 which receives the output becomes 0V, and the output of the charge / discharge circuit 4 becomes 0V.
The voltage becomes V, and 0 V is input to the comparator 5. Since the voltage input to the comparator 5 is lower than the reference voltage of 1V, the voltage of 5V is output. The switch circuit 6 outputs the input voltage of 5V as it is. The amplification degree of the amplifier 7 becomes 0 dB by the control voltage of 5 V which is the output of the switch circuit 6. The audio signal of the video input to the amplifier 7 is output with the same amplitude. The amplifier 8 and the amplifier 9 output the video / audio output of the amplifier 7 as a transmission output signal and a reception output signal, respectively.

【0024】1−2.肉声による送話信号が通常のレベ
ル(−20dBm程度)のとき 増幅器1は肉声による送話信号を増幅し、最大振幅(1
0Vp−p)で出力する。整流回路3は増幅器1の出力
を半波整流回路で直流レベルに変換し、5Vで充放電回
路4に出力する。比較器5は入力電圧が基準電圧である
1Vより高いので、0Vを出力する。スイッチ回路6は
入力された0Vの電圧をそのまま出力する。増幅器7は
スイッチ回路6の出力である0Vの制御電圧により、増
幅度が−20dBになるので増幅器7に入力されたビデ
オの音声信号は20dB減衰されて出力される。増幅器
8は増幅器7の出力を肉声による送話信号に重畳させ
て、送話出力信号を出力する。増幅器9は増幅器7の出
力を入力として、受話出力信号を出力する。
1-2. When the voice transmission signal by the real voice is at a normal level (about -20 dBm) The amplifier 1 amplifies the voice transmission signal by the real voice, and the maximum amplitude (1
Output at 0Vp-p). The rectifier circuit 3 converts the output of the amplifier 1 into a DC level by a half-wave rectifier circuit and outputs it to the charge / discharge circuit 4 at 5V. The comparator 5 outputs 0V because the input voltage is higher than the reference voltage of 1V. The switch circuit 6 outputs the inputted 0V voltage as it is. The amplification degree of the amplifier 7 becomes -20 dB by the control voltage of 0 V which is the output of the switch circuit 6, so that the audio signal of the video input to the amplifier 7 is attenuated by 20 dB and output. The amplifier 8 superimposes the output of the amplifier 7 on the voice-transmitted voice signal and outputs a voice-transmitted output signal. The amplifier 9 receives the output of the amplifier 7 as an input and outputs a reception output signal.

【0025】1−3.1−2の状態から1−1の状態に
移行してから2秒以内のとき 増幅器1および2はそれぞれの入力信号が0Vなので、
出力は0Vである。その出力を入力とする整流回路3に
おいては半波整流回路の出力電圧は0Vであるが、充放
電回路4の出力電圧は下降中で5Vから1Vの間にあ
る。したがって、比較器5には5V以下1V以上の電圧
が入力される。比較器5は入力電圧が基準電圧である1
Vより高いので、0Vを出力する。スイッチ回路6は入
力された0Vの電圧をそのまま出力する。増幅器7はス
イッチ回路6の出力である0Vの制御電圧により、増幅
度が−20dBになるのでビデオの音声信号は20dB
減衰されて出力される。増幅器8、および、増幅器9は
増幅器7の出力を入力として、それぞれ、送話出力信
号、受話出力信号を出力する。
Within 2 seconds after shifting from the state of 1-3.1-2 to the state of 1-1. Since the input signals of the amplifiers 1 and 2 are 0 V, respectively.
The output is 0V. In the rectifier circuit 3 that receives the output, the output voltage of the half-wave rectifier circuit is 0V, but the output voltage of the charging / discharging circuit 4 is falling and is between 5V and 1V. Therefore, a voltage of 5 V or less and 1 V or more is input to the comparator 5. The input voltage of the comparator 5 is the reference voltage 1
Since it is higher than V, 0V is output. The switch circuit 6 outputs the inputted 0V voltage as it is. The amplifier 7 has an amplification degree of -20 dB due to the control voltage of 0 V which is the output of the switch circuit 6, so that the audio signal of the video is 20 dB.
Attenuated and output. The amplifier 8 and the amplifier 9 receive the output of the amplifier 7 and output a transmission output signal and a reception output signal, respectively.

【0026】1−4.局側からの受話信号が通常のレベ
ル(−6dBm程度)のレベルで入力されているとき 増幅器2は局側からの受話信号を増幅し、最大振幅(1
0Vp−p)で出力する。整流回路3は増幅器2の出力
を半波整流回路で直流レベルに変換し、5Vで充放電回
路4に出力する。充放電回路4の出力は5Vで比較器5
に出力される。以後は1−2の状態と同様に増幅器7に
入力されたビデオの音声信号は20dB減衰されて出力
される。
1-4. When the reception signal from the station side is input at a normal level (about -6 dBm) The amplifier 2 amplifies the reception signal from the station side, and the maximum amplitude (1
Output at 0Vp-p). The rectifier circuit 3 converts the output of the amplifier 2 into a DC level by a half-wave rectifier circuit, and outputs it to the charge / discharge circuit 4 at 5V. The output of the charge / discharge circuit 4 is 5V and the comparator 5
Is output to. After that, the audio signal of the video input to the amplifier 7 is output after being attenuated by 20 dB as in the state of 1-2.

【0027】1−5.1−4の状態から1−1の状態に
移行してから2秒以内のとき 動作は1−3の状態と同じなので省略する。
Within 2 seconds after the state of 1-5.1-4 is changed to the state of 1-1. The operation is the same as the state of 1-3, and will be omitted.

【0028】2.自動制御がオフ状態のとき スイッチ回路6の出力が常に5Vであるために、増幅器
7の利得は常に0dBになっている。増幅器7に入力さ
れたビデオの音声信号は減衰されずに出力される。増幅
器8は増幅器7の出力を肉声による送話信号に重畳し
て、送話出力信号を出力する。増幅器9は増幅器7の出
力を局側からの受話信号に重畳して、受話出力信号を出
力する。
2. Since the output of the switch circuit 6 is always 5 V when the automatic control is in the off state, the gain of the amplifier 7 is always 0 dB. The audio signal of the video input to the amplifier 7 is output without being attenuated. The amplifier 8 superimposes the output of the amplifier 7 on the voice-transmitted voice signal and outputs a voice-transmitted output signal. The amplifier 9 superimposes the output of the amplifier 7 on the reception signal from the station side and outputs a reception output signal.

【0029】[0029]

【発明の効果】以上説明したように、本発明によればビ
デオの音声信号が入力されて送話出力信号、受話出力信
号として出力されている状態で、肉声による送話信号、
局側からの受話信号のどちらかが入力されることによ
り、送話出力信号、受話出力信号に含まれるのビデオの
音声信号成分のレベルが下がる。それにより肉声による
送話信号、局側からの受話信号がビデオの音声信号に妨
げられずにそれぞれ送話出力信号、受話出力信号として
出力される。
As described above, according to the present invention, in the state where the audio signal of the video is input and is output as the transmission output signal and the reception output signal, the transmission signal by the real voice,
The level of the audio signal component of the video included in the transmission output signal and the reception output signal is lowered by inputting one of the reception signals from the station side. As a result, the voice-transmitted signal by the real voice and the voice-received signal from the station side are output as the voice-transmitted output signal and the voice-received output signal, respectively, without being disturbed by the video audio signal.

【0030】また肉声による送話信号あるいは局側から
の受話信号が入力されている状態で、次に肉声による送
話信号および局側からの受話信号が入力されなくなって
も、設定された時定数により、しばらくの間(2秒)は
ビデオの音声信号成分のレベルは下がったままである。
これにより、通話音声の合い間にビデオの音声信号が割
り込んで耳ざわりになることが防止され、スムーズな通
話を継続することができる。
Further, in the state where the voice-transmitted signal by the real voice or the voice-received signal from the station side is input, even if the voice-transmitted signal by the real voice and the voice-received signal from the station side are not input next, the set time constant is set. Therefore, the level of the audio signal component of the video remains lowered for a while (2 seconds).
As a result, it is possible to prevent the audio signal of the video from interfering with the audibility of the audio during the interval between the phonetic sounds, and it is possible to continue a smooth phone call.

【0031】自動制御にオン/オフ切り替え信号によ
り、肉声による送話信号および局側からの受話信号の入
力に関わらずビデオの音声信号成分が減衰されずに送話
出力信号および受話出力信号として出力される状態に設
定することができる。
By the ON / OFF switching signal for automatic control, the audio signal component of the video is output as the transmission output signal and the reception output signal without being attenuated regardless of the input of the transmission signal by the real voice and the reception signal from the station side. Can be set to the state that is set.

【0032】具体的には自動制御のオン/オフ切り替え
信号は通話中/非通話中の状態により変更される。通話
中は自動制御をオンにするが、非通話中はオフにしてマ
イクからの音声によりビデオの音声が中断されないよう
にして端末でビデオを見ることができるようにしてい
る。
More specifically, the ON / OFF switching signal for automatic control is changed depending on the state of talking / not talking. The automatic control is turned on during a call, but turned off during a non-call so that audio from the microphone does not interrupt the audio of the video so that the terminal can watch the video.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の一実施例のブロック図FIG. 1 is a block diagram of an embodiment of the present invention.

【図2】図1整流回路の回路図FIG. 2 is a circuit diagram of the rectifier circuit shown in FIG.

【符号の説明】[Explanation of symbols]

1 増幅器 2 増幅器 3 整流回路 4 充放電回路 5 比較器 6 スイッチ回路 7 増幅器 8 増幅器 9 増幅器 1 amplifier 2 amplifier 3 rectifier circuit 4 charge / discharge circuit 5 comparator 6 switch circuit 7 amplifier 8 amplifier 9 amplifier

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 肉声による送話信号を増幅する第1の増
幅器と、 局側からの受話信号を増幅する第2の増幅器と、 前記第1および第2の増幅器の出力を直流電圧に変換し
て、常にどちらか電圧の高い方を出力する整流回路と、 前記清流回路の出力を充電し、前記整流回路の出力がな
くなると放電し、放電時はある時定数をもって出力電圧
が減少する充放電回路と、 前記充放電回路の出力を入力とし、基準電圧に対して、
入力電圧が高いと第一のレベルの電圧を出力し、低いと
第二のレベルの電圧を出力する比較器と、 前記比較器の出力を入力として、入力と同じ電圧をその
まま出力する状態と入力電圧に関わらず第二のレベルの
電圧のみを出力する状態を、制御信号により切り替える
スイッチ回路と、 ビデオ等の音声信号を入力とし、前記スイッチ回路の出
力を制御入力とし、制御入力が第二のレベルの電圧の時
は聴取するのにちょうど良い出力になるような利得であ
り、第一のレベルの電圧の時は聴取するのに困難なほど
振幅を小さくする利得で、ビデオ等の音声信号を増幅す
る第3の増幅器と、 前記第3の増幅器の出力を肉声による送話信号に重畳す
る回路と、 前記第3の増幅器の出力を局側からの受話信号に重畳す
る回路と、を含む音声回路。
1. A first amplifier which amplifies a voice transmission signal by a real voice, a second amplifier which amplifies a reception signal from a station side, and outputs the outputs of the first and second amplifiers to a DC voltage. A charging / discharging circuit that constantly outputs the higher voltage, and that charges the output of the clear circuit, discharges when the output of the rectification circuit is exhausted, and decreases the output voltage with a certain time constant during discharging. Circuit, with the output of the charge and discharge circuit as an input, with respect to a reference voltage,
A comparator that outputs a first level voltage when the input voltage is high and a second level voltage when the input voltage is low, and a state in which the output of the comparator is used as an input and the same voltage as the input is directly output. A switch circuit that switches only the second level voltage regardless of the voltage by a control signal and an audio signal such as video is input, the output of the switch circuit is the control input, and the control input is the second At the level voltage, the gain is such that the output is just right for listening, and at the voltage at the first level, the amplitude is so small that it is difficult to hear. A voice including a third amplifier that amplifies, a circuit that superimposes an output of the third amplifier on a voice transmission signal by a real voice, and a circuit that superimposes an output of the third amplifier on a reception signal from a station side. circuit.
【請求項2】 前記第1および第2の増幅器はそれぞれ
送話信号,受話信号を最大振幅レベルまで増幅可能であ
ることを特徴とする請求項1に記載された音声回路。
2. The voice circuit according to claim 1, wherein the first and second amplifiers are capable of amplifying a transmission signal and a reception signal, respectively, up to a maximum amplitude level.
JP226493A 1993-01-11 1993-01-11 Audio circuit Expired - Fee Related JP2927130B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP226493A JP2927130B2 (en) 1993-01-11 1993-01-11 Audio circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP226493A JP2927130B2 (en) 1993-01-11 1993-01-11 Audio circuit

Publications (2)

Publication Number Publication Date
JPH06209378A true JPH06209378A (en) 1994-07-26
JP2927130B2 JP2927130B2 (en) 1999-07-28

Family

ID=11524519

Family Applications (1)

Application Number Title Priority Date Filing Date
JP226493A Expired - Fee Related JP2927130B2 (en) 1993-01-11 1993-01-11 Audio circuit

Country Status (1)

Country Link
JP (1) JP2927130B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007261179A (en) * 2006-03-29 2007-10-11 Konica Minolta Holdings Inc Voltage control apparatus of liquid jet head, voltage control method of liquid jet head and liquid jet device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007261179A (en) * 2006-03-29 2007-10-11 Konica Minolta Holdings Inc Voltage control apparatus of liquid jet head, voltage control method of liquid jet head and liquid jet device

Also Published As

Publication number Publication date
JP2927130B2 (en) 1999-07-28

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